The present-invention relates generally to telescopes of the type commonly used to observe and photograph celestial objects. The present invention relates more particularly to a telescope system which can be easily upgraded from friction lock mounting to manual worm drive, and from manual worm drive to motor drive. Further, the present invention comprises a mount which facilitates enhanced below the horizon and zenith viewing a motor vibration isolation system, an adjustable worm drive, a tripod having detents which hold the legs in a deployed position thereof during handling of the tripod, a cam lock for maintaining a desired length of the tripod legs and an X-Y adjustable finder scope.
Telescopes for observing and/or photographing celestial objects such as planets, moons, stars, galaxies, asteroids, comets, nebulae, and the like are well known. Such telescopes range in size from small, readily portable ones to large fixed ones which are permanently located in observatories. The smaller telescopes are commonly used by students, hobbyists and amateur astronomers. The larger telescopes are generally only used by researchers and professional astronomers.
Common types of telescopes include refractor telescopes, reflector telescopes, Schmidt-Cassegrain telescopes and Maksutov-Cassegrain telescopes. Refractor telescopes have a light collecting objective lens which focuses the collected light upon an eyepiece. The eyepiece, in cooperation with the objective lens, provides the desired magnification.
A reflector telescope utilizes a primary mirror to collect light and a secondary mirror to reflect the collected light through an opening in the telescope tube to an eyepiece. The eyepiece is mounted upon the tube, typically near the front of he tube, and is positioned orthogonal to the tube. The eyepiece cooperates with the primary mirror to provide the desired magnification.
Schmidt-Cassegrain telescopes are similar to reflector telescopes, except that the secondary mirror of a Schmidt-Cassegrain telescope reflects the collected light through an opening in the primary mirror instead of through an opening in the tube. In this manner, the eyepiece can be located directly behind the primary mirror, which is convenient for some types of viewing and photography. Additionally, light enters a Schmidt-Cassegrain telescope through a thin, two-side a spheric lens, known as a correction plate. Further, the secondary mirror is convex, so as to increase the effective focal length of the primary mirror.
Maksutov-Cassegrain telescopes are similar to Schmidt-Cassegrain telescopes, except that in Maksutov-Cassegrain telescopes light enters the telescope through a meniscus lens and an oversize primary mirror is used to provide an unvignetted field of view.
In viewing celestial objects with any type of telescope, it is necessary to continually move the telescope, so as to maintain the telescope in desired alignment with the celestial object. This is necessary to compensate for the rotation of the earth with respect to the cosmos. Thus, such continual realignment of the telescope maintains the desired celestial object within the field of view of the telescope as the earth rotates about its axis.
Smaller, portable telescopes of the reflector, refractor, Schmidt-Cassegrain, Maksutov-Cassegrain or any other desired type are typically mounted upon a tripod to facilitate portability and use of the telescope upon uneven outdoor surfaces, such as upon the ground, upon paved surfaces such as roads or parking lots, or upon any other desired surface.
Two different types of mounts, altitude azimuth and equatorial, are commonly used to removably attach a telescope to a tripod. Altitude azimuth (altazimuth) mounts provide a comparatively rigid and steady mount for the telescope, but are more difficult to maintain in alignment with a desired celestial object when the telescope is being aimed manually. Altitude azimuth mounts have only two perpendicular axes of rotation, which make altitude azimuth telescopes inherently more rigid and stable than equatorial telescopes. The altitude axis of rotation allows the telescope to pivot with respect to the mount about a horizontal axis and the azimuth axis of rotation allows the telescope to pivot about a vertical axis. In order to maintain alignment of a telescope having an altitude azimuth mount with respect to a desired celestial object, it is generally necessary to move the telescope about both the altitude and azimuth axes, since the position of celestial objects generally varies in both altitude and azimuth as the earth rotates.
Equatorial mounts facilitate easier maintenance of alignment of the telescope with a desired celestial object, since the telescope must only be moved about a single axis so as to maintain such alignment. In an equatorial mount, two orthogonal axis are configured such that one of the two axes can easily be aligned so as to be parallel to the axis of rotation of the earth. Once such alignment with the earth""s axis of rotation is accomplished, then it is merely necessary to move the telescope about the other axis, so as to maintain alignment of the telescope with a desired celestial object. Thus, with an equatorial mount only a single axis of the telescope needs to be moved in order to maintain such alignment.
However, in an equatorial mount it is necessary to provide two additional orthogonal axis of alignment (similar to those of an altitude azimuth mount) in order to facilitate alignment of one axis so as to be parallel to the earth""s axis of rotation. Thus, an equatorial mount actually comprises an altitude azimuth mount plus two additional axes and thus has a total of four different alignment axes. Because the equatorial mount comprises four different alignment axis, and because each axis inherently decreases the stability of the mount, it is difficult to manufacture an equatorial mount which is as stable as a comparable altitude azimuth mount (which has only two axes of alignment).
Portable, tripod mounted telescopes have evolved to the point where they are comparable in quality to the larger, fixed telescopes of observatories. With the advent of precise alignment control and electronic imaging, it is now possible to use such portable telescopes to take pictures of celestial objects which could only be photographed by observatories just a few years ago.
Although such contemporary portable telescopes have proven generally useful for their intended purposes, they do possess substantial deficiencies. For example, contemporary portable telescopes are not easily upgradeable, they are typically susceptible to vibration caused by drive motors, they cannot always be oriented as desired, they utilize tripods which are unreliable or difficult to use, and they have a finder scope which is difficult to align with the telescope.
Frequently, a telescope is purchased in a basic, or less expensive configuration, and it is later desired to upgrade the telescope so as to provide desirable features and enhanced functionality. For example, it is common for an amateur astronomer to first purchase a small refractor telescope which has a mount which utilizes friction locks to maintain the desired orientation of the telescope. The telescope is aimed at a desired celestial body by loosening the friction locks and manually manipulating the telescope with respect to the tripod, so as to effect the desired alignment. The friction mounts are then tightened to prevent the telescope from moving.
However, as those skilled in the art will appreciate, such friction lock mounts are clumsy and extremely difficult to use. Fine adjustments in alignment, which are frequently necessary so as to maintain a desired celestial object within the field of view of the telescope, are extremely difficult to make when utilizing friction lock mounts. Usually, manual manipulation of the telescope results in uneven, jerky movements of the telescope. It is almost impossible to take long exposure photographs with a telescope having friction mounts. Further, the very act of tightening a friction lock (which is intended to maintain desired alignment) frequently causes undesirable misalignment of the telescope. Thus great care must be taken in the use of such friction lock mounts so as to maintain desired alignment of the telescope.
Because of the difficulty of maintaining desired alignment of the telescope with respect to a celestial object being observed or photographed, it is frequently desirable to upgrade the telescope to utilize manual worm drives, rather than friction lock mounts. To change the altitude or azimuth alignment of a telescope which utilizes manual worm drives, the user merely turns a knob associated with the desired axis to be adjusted, so as to effect comparatively smooth rotation of the telescope about that axis. For example, to change the altitude alignment of the telescope, the user merely turns the altitude manual worm drive knob. The worm drive provides gear reduction, such that turning the knob results only in very minute changes in altitude adjustment, thus facilitating very precise and easy alignment of the telescope is obtained. The worm drive also provides a much greater degree of stability as compared to a friction drive. In a worm drive, the adjustment knob is attached to a worm, which rotates a worm gear as the knob is turned. Such a worm/worm gear arrangement is inherently stable and tends to resist movement of the telescope unless the adjustment knob is turned. With a manual worm drive, it is even possible for a very patient user to maintain sufficient alignment of the telescope to facilitate long exposure celestial photography.
However, such manual adjustment of the telescope requires constant attention, particularly during celestial photography. Thus, it is desirable to further upgrade the telescope by motorizing the worm drive, so as to eliminate the need for such constant manual adjustment. When utilizing a motorized worm drive, a computer may be utilized to provide control signals to the motors, so as to continuously effect the desired alignment. Further, the computer may further be utilized to find the desired celestial object, as well as to aid in an initial alignment of the telescope.
Thus, it is clear that a series of consecutive upgrades to a telescope is frequently desirable. However, effecting such upgrades with contemporary telescopes is typically a difficult, costly and time consuming endeavor. Quite often, the telescope or the mount must be modified, so as to accommodate such upgrades. As such, it is desirable to provide a telescope system which readily accommodates upgrading of the telescope mount from friction lock mounts to manual worm drives and from manual worm drives to motorized worm drives in a manner which is simple, convenient, and comparatively inexpensive.
Another problem commonly associated with contemporary telescopes is that those contemporary telescopes utilizing motor drives are undesirably subject to vibration caused by operation of the motors. As those skilled in the art will appreciate, the electric motors associated with such motor drives can operate at comparatively high speeds, e.g., occasionally as high as 15,000 rpm. At such high speeds, any slight imbalance in the motor tends to cause the motor to vibrate, and thus transmit such vibration through the drive motor assembly and the mount, to the telescope. It will be appreciated that even minute vibrations of the telescope are highly undesirable when high magnifications are used. When utilizing such high magnifications, even the slightest movement of the telescope will cause the viewed celestial object to move appreciably within the field of view. Indeed, excessive vibration will make the telescope unusable for celestial photography at higher magnifications. Thus, it is desirable to isolate the motor from the telescope, so as to mitigate vibration of the telescope caused by the motor.
Another problem commonly associated with contemporary telescopes is that during below the horizon and during zenith viewing, it is frequently difficult to orient contemporary telescopes at the desired angle. Below the horizon viewing is viewing in which the telescope is oriented such that it points in a direction below horizontal, i.e., points somewhat downwardly. Below the horizon viewing is also frequently used during terrestrial observations, particularly when the telescope is situated at a higher elevation than the object being observed, such as when the telescope is located within a tall building or upon a hill. Zenith viewing occurs when the telescope is oriented such that it is substantially vertical, i.e., aimed directly overhead. As discussed above, contemporary telescope mounts inhibit such viewing. Further, it is necessary to continually vary the alignment of the telescope, so as to maintain a desired celestial object within the field of view. Occasionally, particularly during celestial photography, it is desirable to maintain the celestial object within the field of view as long as possible. Thus, it is occasionally desirable to maintain the desired celestial object within the field of view by orienting the telescope for below the horizon and/or zenith viewing.
As those skilled in the art will appreciate, contemporary mounts tend to undesirably limit the angle at which below the horizon and zenith viewing is possible. Such contemporary mounts interfere with desired movement of the telescope during below the horizon and zenith viewing such that the telescope undesirably abuts the mount when moved to its extreme limit of travel during such viewing. Thus, it is desirable to provide a telescope mount which facilitates below the horizon and zenith viewing at enhanced angles.
As discussed above, portable telescopes are frequently mounted upon tripods. Although such tripods provide an inexpensive and convenient means for mounting the telescope, contemporary tripods do possess deficiencies. For example, when a contemporary tripod is picked up, as when moving the telescope from one location to a nearby location, or when disassembling the telescope for transport, the legs of the tripod tend to fold in from their extended or deployed positions undesirably. Such folding, when merely moving the telescope from one location to a nearby location, necessitates that the user redeploy the tripod legs at the new location. As those skilled in the art will appreciate, such redeploying of the telescope legs is difficult, particularly when a single person is attempting to move the telescope. Thus, it would be desirable to provide a tripod which maintains the legs thereof in a deployed position until the user desires that the legs be folded or stowed.
Yet another problem commonly associated with contemporary telescopes is that of unreliable locking mechanisms for maintaining the tripod legs at the desired length thereof. Many tripods utilize telescoping legs, so as to facilitate easy storage and transportation thereof. Such telescoping tripod legs may be adjusted to the desired length and locked in place. However, the locks of contemporary telescopes are frequently unreliable. When such a lock fails, then one leg of the tripod collapses, resulting in loss of alignment of the telescope with the object being viewed and possibly resulting in substantial damage to the telescope. Thus, it is desirable to provide a positively acting, reliable lock for telescoping tripod legs.
Yet another disadvantage associated with contemporary telescopes is the manner in which finder scopes thereof are mounted to the telescope and adjusted with respect thereto. Contemporary finder scopes are typically attached to telescopes utilizing two brackets which are spaced apart along the length of the finder scope and which attach rigidly to the telescope. The contemporary finder scope is held in position with respect to each of the two brackets by three set screws which threadedly engage the bracket and which bear upon the finder scope. The finder scope is aligned with the telescope by loosening at least one of the three set screws of a bracket and then tightening one or two of the other set screws of the same bracket.
However, this process is not intuitive in that it tends to move the finder scope in two orthogonal directions (as related to a X-Y coordinate system) simultaneously. That is, such contemporary finder scopes do not facilitate movement thereof in only a selected one of two orthogonal directions. Thus, a contemporary finder scope tends to move in both the X and Y direction when any adjustment is made thereto. Such operation of the finder scope can be extremely confusing, particularly for novices. Thus, alignment of a contemporary finder scope can require an undesirably excessive amount of time.
As those skilled in the art will appreciate, it is necessary to properly align the finder scope with the telescope, so as to facilitate aiming of the telescope at a desired object. The finder scope must be in alignment with the telescope in order to facilitate alignment of the telescope with the desired celestial object. Thus, it is desirable to provide a mount for a finder scope which facilitates adjustment of the finder scope in only a single X-Y direction at a time, so as to simplify alignment thereof with respect to a telescope.
The present invention specifically addresses and alleviates the above-mentioned deficiencies associated with the prior art. More particularly, the present invention comprises a telescope system of the type commonly used to observe and photograph celestial objects. The telescope system comprises a telescope, a tripod supporting the telescope, and a mount attaching the telescope to the tripod in a manner which facilitates rotation of the telescope about first and second generally orthogonal axis.
According to the present invention, the telescope system facilitates easy, convenient, and comparatively inexpensive upgradeability from friction lock mounts to manual worm drives and from manual worm drives to motor worm drives. The telescope system of the present invention is constructed so as to mitigate vibration from the motor, so as to facilitate enhanced viewing and photography. The mount is configured so as to facilitate below the horizon and zenith viewing and photography at enhanced angles. The tripod is constructed so as to maintain the legs thereof in either the deployed or stowed positions, as desired. The legs of the tripod comprise locks which are positive acting and reliable. The finder scope of the present invention is constructed so as to facilitate alignment thereof with the telescope by moving the finder scope in a single X-Y direction as an alignment adjustment is being performed, thereby substantially simplifying the alignment process.
The mount comprises a base pivotally attached to the tripod to define the first or azimuth axis, two arms extending from the base to which the telescope is pivotally attached to define the second or altitude axis, a first cutout formed in the mount for providing clearance to the telescope when the telescope is oriented for below the horizon viewing, so as to enhance an angle at which the telescope is capable of being oriented during below the horizon viewing, and a second cutout formed in the mount for providing clearance to the telescope when the telescope is oriented for zenith viewing, so as to enhance an angle at which the telescope is capable of being oriented during zenith viewing. The first and second cutouts are preferably formed in either the base or are formed in a fork defined by the two arms. The first and second cutouts may likewise be formed in any portion of the mount which undesirably limits movement of the telescope. The arms preferably extend from the base at an angle of between approximately 30xc2x0 and approximately 60xc2x0, preferably approximately 45xc2x0, with respect to vertical.
Further, and according to the present invention, an UPGRADEABLE telescope system comprises a first pivot attaching the telescope to the mount for facilitating rotation of the telescope about the azimuth axis and a-second pivot attaching the mount to the tripod for facilitating rotation of the telescope about the altitude axis. Thus, the first pivot preferably defines a generally horizontal axis of rotation, i.e., an altitude axis, and the second pivot defines a generally vertical axis of rotation, i.e., an azimuth axis. A first friction lock is configured to mitigate rotation of the telescope about the first axis. The first friction lock is configured to removably attach a first worm drive thereto. Similarly, a second friction lock is configured to mitigate rotation of the telescope about the second axis. The second friction lock is likewise configured to removably attach a second worm drive thereto. Thus, the first and second friction locks are configured so as to facilitate easy, convenient, and inexpensive upgrade thereof from friction lock mounting to manual or motorized worm drives.
The first and second friction locks comprise a friction lock housing, a knob which is rotatable with respect to the friction lock housing so as to effect engagement of the friction lock, and a plurality of threaded openings formed in the friction lock housing for receiving threaded fasteners so as to removably attach a worm drive to the friction lock housing.
Each of the first and second friction locks preferably further comprise a spacer located intermediate the knob and the friction lock housing. The spacer provides room for the worm drive when the spacer is removed. Thus, according to the preferred embodiment of the present invention, a portion of a worm drive may optionally be located intermediate the knob and the friction lock housing. The worm drive is removably attachable to each of the first and second friction lock housings so as to effect either manual or motorized rotation of the telescope about the altitude and azimuth axis.
Each worm drive comprises a housing which is configured to removably attach a motor so as to facilitate motorized operation thereof. According to the preferred embodiment of the present invention, each worm drive housing comprises at least one threaded opening for receiving a threaded fastener, so as to removably attach a motor to the worm drive housing. Thus, according to the present invention, a motor is removably attachable to each worm drive housing so as to effect rotation of the telescope about the altitude and azimuth axes thereof.
According to the preferred embodiment of the present invention, each worm drive comprises a worm gear coupled to effect rotation of the telescope when the worm gear rotates, a worm coupled to effect rotation of the worm gear when the worm rotates, and a knob coupled to effect rotation of the worm when the knob rotates. The knob is manually rotatable, so as to facilitate manual adjustment of the altitude and azimuth axis. According to the preferred embodiment of the present invention, the worm gear of each worm drive is configured such that it rotates upon a shaft without effecting rotation of the shaft when a knob of the friction lock to which the worm drive is attached is loose, and such that the worm gear effects rotation of the shaft when the knob of the friction lock to which the worm drive is attached is tight. Rotation of the shaft effects rotation of the telescope. Further, according to the preferred embodiment of the present invention, two metal washers are disposed upon the shaft. One metal washer is located upon each side of the worm gear and is configured so as to rotate with the shaft. Thus, the two metal washers and the worm gear define a clutch which is controlled by the knob, such that the clutch engages when the knob is tightened and disengages when the knob is loosened.
A polystyrene friction washer is preferably located intermediate each metal washer and the worm gear and is configured so as to rotate independently with respect to the shaft. The polystyrene friction washers tend to provide a generally constant coefficient of friction between the metal washers and the worm gear when the drive knob is tight. The polystyrene friction washers tend to provide a generally constant coefficient of friction regardless of contamination thereof with oily or greasy substances such as lubricants.
Optionally, a hand-held controller controls the motors, so as to facilitate aiming of the telescope at a desired celestial object. The hand held controller comprises either a key pad for facilitating input of commands to move the telescope in altitude and azimuth, or alternatively comprises a joy stick for facilitating input of commands to move the telescope in altitude and azimuth. Optionally, the hand-held controller comprises a microprocessor configured to aim the telescope at a desired celestial object when either a designation, e.g., name or number, of the celestial object or coordinates of the celestial object are entered into the hand-held controller.
The telescope system of the present invention preferably comprises a tripod having a head and three legs pivotally attached to the head and extending downwardly from the head. The three legs have a stowed position and a deployed position. Preferably, a detent is formed upon each leg and is configured so as to releasably hold each leg in the deployed position thereof. As is common in contemporary tripods, the legs are preferably configured so as to telescope in order to vary the length thereof, as desired.
The detent may be formed upon either the head or upon each leg. The detent preferably comprises a protrusion formed upon either the head or upon each leg. Thus, each detent comprises either a protrusion formed upon the head and a corresponding generally flat surface formed upon each leg, such that the flat surface abuts the protrusion and tends to compress the protrusion as the leg is moved from the deployed position to the stowed position thereof, or the detent alternatively comprises a protrusion formed upon each leg and a corresponding generally flat surface formed upon the head for each protrusion, such that the flat surface abuts each protrusion and tends to compress the protrusion as the leg is moved from the deployed position to the stowed position thereof. Preferably, each detent is also configured to releasably hold the leg in the stowed position thereof. Preferably, the tripod further comprises a first stop formed upon the head for defining the deployed position of each leg and a second stop formed upon the head for defining the stowed position of each leg. The first and second stops limit the range of travel of the legs so as to define the deployed and stowed positions thereof.
Each of the legs of the tripod preferably comprise a lock for maintaining the leg at a desired length. The lock preferably comprises a lever having a cam formed thereon. The lever is pivotally attached to the leg section having the larger diameter of the two telescoping sections thereof, e.g., the upper section. A pusher is formed of a substantially rigid material and the cam is configured such that the cam pushes the pusher toward the second leg section when the lever is moved. A friction pad is located upon the pusher and comprises a substantially resilient material. The friction pad is configured to contact the second leg section when the pusher is pushed there toward, so as to frictionally engage the second leg section and thereby mitigate movement of the second leg section with respect to the first leg section.
The telescope system of the present invention preferably further comprises a finder scope which is attached to the telescope for aiding in alignment of the telescope with respect to a desired celestial object which is to be observed or photographed with the telescope. The finder scope comprises a tube having proximal and distal ends, an eyepiece located at the proximal end of the tube, an objective lens located at the distal end of the tube, and first and second brackets spaced apart along the tube for adjustably attaching the tube to the telescope. The first bracket comprises a first pair of parallel knife edges defining a first opening and the second bracket similarly comprises a second pair of parallel knife edges defining the second opening. Each pair of knife edges define pivot about which the finder scope can rotate with respect to the telescope. The tube is located within the first and second openings, such that it extends there through, and the first and second pairs of knife edges are oriented generally orthogonally to one another, so as to facilitate adjustment of the finder scope in two generally orthogonal directions. The first mount is preferably located near the proximal end of the tube and the second mount is preferably located near the distal end of the tube.
According to the preferred embodiment of the present invention, a first pair of opposed set screws threadedly engage the first mount and are located upon opposite sides of the tube, so as to effect movement of the tube within the first opening. Similarly, a second pair of opposed set screws threadedly engage the second mount and are located upon opposite sides of the tube, so as to effect movement of the tube within the second opening. The first and second mounts are preferably configured such that movement of the tube within the first opening causes rotation of the tube about a first axis and movement of the tube within the second opening causes rotation of the tube about a second axis, wherein the first and second axis are generally orthogonal to one another. According to the preferred embodiment of the present invention, the first axis is located proximate the second opening and is generally parallel to the knife edges of the second opening and the second axis is located proximate the first opening and is generally parallel to the knife edges of the first opening.
Thus, according to the present invention, a method for aligning a finder scope with respect to a telescope, so as to facilitate subsequent use of the finder scope in alignment of the telescope with respect to a celestial object to be observed or photographed with the telescope comprises the steps of moving the finder scope along a first pair of knife edges defining a first opening through which the finder scope extends, so as to align the finder scope in a first axis with respect to the telescope, and moving the finder scope along a second pair of knife edges defining a second opening through which the finder scope extends, so as to align the finder scope in a second axis with respect to the telescope. The steps of moving the finder scope along the first and second pairs of knife edges preferably comprise sliding the finder scope along the first and second pairs of knife edges. More particularly, the steps of moving the finder scope along the first and second pairs of knife edges preferably comprise loosening a first set screw to facilitate movement of the finder scope with respect to the first pair of knife edges, tightening a second set screw such that the second set screw causes the finder scope to move with respect to the first pair of knife edges, loosening a third set screw to facilitate movement of the finder scope with respect to the second pair of knife edges, and tightening a fourth set screw such that the fourth set screw causes the finder scope to move with respect to the second pair of knife edges. After the second and fourth set screws have been tightened sufficiently, so as to position the finder scope in desired alignment with the telescope, then the first and third set screws are tightened, as necessary, so as to lock the finder scope into alignment with the telescope.
Further, according to the present invention, a first shaft is rigidly attached to the telescope and a second shaft is rigidly attached to the base of the mount. The first shaft is pivotally attached to one of the two arms of the mount so as to define a first axis of two generally orthogonal axes is and the second shaft is rigidly attached to the base and pivotally attached to the tripod so as to define a second axes of the two generally orthogonal axes. At least one worm drive effects desired movement of the telescope with respect to the tripod. Each worm drive comprises a worm gear formed upon one of the first and second shafts, a worm having first and second ends engaging each worm gear. A pair of resilient supports facilitate mounting of each worm. One resilient support is located proximate the first end of each worm and the other resilient support is located proximate the second end of each worm. The resilient supports provide shock/vibration isolation of the worm with respect to the telescope. The resilient supports preferably comprise rubber, preferably Shore A 50 silicone rubber. Those skilled in the art will appreciate that various other resilient polymer materials and the like are likewise suitable.
Each of the resilient supports preferably comprise a body having a flat side and an opening form through the body. The worm extends through the opening. One resilient support facilitates mounting of the worm at each end of the worm. Further, a bushing is located within the opening of the body of each support, for facilitating rotation of the worm with respect to the support. The bushing is preferably comprised of a rigid polymer materials, such as polyethylene terephthalate (PET).
According to the preferred embodiment of the present invention, each worm drive further comprises two set screws, one set screw for adjusting the position of each of the two supports with respect to the worm gear, so as to facilitate desired engagement of the worm with the worm gear. The worm drive preferably further comprises a pusher block for each support configured such that one of the set screws pushes against the pusher block and the pusher block pushes against the support. The pusher block is preferably comprised of acrylonitrile butadiene styrene resin (ABS). Adjusting the desired set screw causes the pusher block to move in a manner which effects corresponding movement of the associated support, thereby facilitating adjustment of the position of the worm with respect to the worm gear. Thus, both ends of the worm can be adjusted so as to facilitate proper alignment of the worm with respect to the worm gear, as well as the desired degree of engagement therewith.
Further, according to the present invention, each worm gear comprises oil impregnated, copper-steel powdered metal and each worm comprises bronze. Each worm gear preferably comprises copper-steel powdered metal in compliance with specification MTIS FC-0208-50. The first and second shafts preferably comprise steel. Further, according to the preferred embodiment of the present invention, at least one bronze bushing (preferably two bronze bushings) is positioned about each of the first and second shafts to facilitate rotation thereof. Further, according to the present invention, the motors for the worm drives preferably comprise electric motor assemblies. Each electric motor assembly preferably comprises a housing, a platform located within the housing, a plurality of first resilient shock/vibration mounts attaching the platform to the housing, an electric motor located upon the platform, and a plurality of second resilient shock/vibration mounts attaching the motor to the platform.
According to the present invention, a plurality of fasteners attach the platform to the housing. The plurality of first resilient shock/vibration mounts comprise two o-rings positioned around each fastener, so as to capture a portion of the platform there between. The housing preferably comprises first and second housing sections and the fasteners attach the first and second housing sections together.
The electric motor preferably comprises a boss form about a shaft of the electric motor at each end thereof. The platform preferably comprises two clamps, one clamp configured to hold each boss. The plurality of second resilient shock/vibration mounts preferably comprised two o-rings, wherein one o-ring is located around each bossed and is captured by each clamp. Alternatively, one or both of mounts comprise a resilient bracket or plate configured to mount the motor to the platform.
Preferably, a reduction gear assembly is mounted upon the platform for facilitating reduction in the rotational speed provided by the motor to the worm drive, while also increasing the torque thereof.
Thus, the present invention provides an easily upgradeable telescope system having improved vibration isolation with respect to the motor drives thereof. An improved tripod is provided which desirably maintains the legs in the stowed or deployed positions thereof and which reliably locks the legs in the desired extended position thereof. An improved finder scope facilitates easy alignment thereof with the telescope.